Generally the LM drive is taken to be the faster drive, even though it is an older model. The seek times for the LM are unmatched by ANY IDE drive....coming in at a whopping 7ms. No other drive comes close. It has been said that this is because the drive is internally a SCSI system, with an IDE interface on the back.
The AS drive is the latest model, and although its sustained transfer rates are better than the LM due to a larger platter size, its real world performance isn't quite up to the level the LM reached. That being said, the AS is still a very fast drive and a top performer.
With the prices you have given, I would probably go for the Quantum drive, as long as it is the same size or larger than the price given for the IBM drive. The IBM may be a tad faster, but I've always felt that Quantum drives are a little more reliable. You can do a direct comparison between the drives' performance over at
Storage Review.